The bug

The colormaps for all the leaves seem to have been swapped around. This results in many odd looking biomes, with some of the most extreme climates having significant clashes.

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Block	Intended colormap (1.21.51)	Bugged colormap (1.21.60.24 Preview)
Oak Leaves	■Foliage	■Birch
Spruce Leaves	■Evergreen	■Foliage
Birch Leaves	■Birch	■Evergreen
Jungle Leaves	■Foliage	■Birch
Acacia Leaves	■Foliage	■Birch
Dark Oak Leaves	■Foliage	■Birch
Mangrove Leaves	■Foliage	■Birch
Cherry Leaves	N/A	N/A
Azalea Leaves	N/A	N/A
Flowering Azalea Leaves	N/A	N/A
Pale Oak Leaves	N/A	N/A
Vines	■Foliage	■Birch

Exception

When the video option "Fancy Leaves" is enabled, leaves will use their correct colormaps, but only within snowy biomes. This is likely related to the fact that leaves turn white when it's snowing.

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